EP1428811A1

Azeotropic compositions comprising 1,1,1,2,3,3,3-heptafluoropropane and processes using said compositions

Abstract

An azeotropic composition, comprising: (a) CF3CHFCF3; and (b) HF; wherein said HF is present in an amount effective to form an azeotropic combination with said CF3CHFCF3. Also provided is a process for producing compositions comprising (c1) a compound selected from the group consisting of CF3CHFCF3, CF3CH2CF3 and CHF2CH2CF3 and (c2) at least one saturated compound selected from halogenated hydrocarbons and ethers having the formula         CnH2n+2-a-bClaFbOc wherein n is an integer from 1 to 4, a is an integer from 0 to 2n+1, b is an integer from 1 to 2n+2-a, and c is 0 or 1, provided that when c is 1 then n is an integer from 2 to 4, and provided that component (c2) does not include the selected component (c1) compound wherein the molar ratio of component (c2) to component (c1) is between about 1:99 and a molar ratio of HF to component (c1) in an azeotrope or azeotrope-like composition of component (c1) with HF, comprising: (A) combining (i) said azeotrope or azeotrope-like composition with (ii) at least one fluorination precursor compound wherein the precursor component (ii) is the fluorination precursor to component (c2); and (B) reacting a sufficient amount of the HF from the azeotrope or azeotrope-like composition (i) with precursor component (ii) to provide a composition containing components (c1) and (c2) in said ratio. Also provided is A composition comprising: (c1) a compound selected from the group consisting of CF3CHFCF3, CF3CH2CF3 and CHF2CH2CF3; and (c2) at least two saturated compounds selected from halogenated hydrocarbons and ethers having the formula:         CnH2n+2-a-bClaFbOc wherein n is an integer from 1 to 4, a is an integer from 0 to 2n+1, b is an integer from 1 to 2n+2-a, and c is 0 or 1, provided that when c is 1 then n is an integer from 2 to 4, and provided that component (c2) does not include the selected component (c1) compound and provided that c is 1 for at least one of the component (c2) compounds, wherein the molar ratio of component (c2) to component (c1) is between 1:99 and 41.3:58.7 when component (c1) is CF3CHFCF3, between 1:99 and 59:41 when component (c1) is CF3CH2CF3, and between 1:99 and 84:16 when component (c1) is CHF2CH2CF3.

EP1428811A1, drawing sheet 1
Sheet 1 of 2

Term

Term ended

Projected expiry passed 18 February 2018, 8.6 years ago.

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9 claims: 5 independent, 4 dependent

  1. 1
    An azeotropic composition, comprising:(a) CF 3 CHFCF 3 ;and (b) HF;wherein said HF is present in an amount effective to form an azeotropic combination with said CF 3 CHFCF 3 .
  2. 3
    A process for producing compositions comprising (c1) a compound selected from the group consisting of CF 3 CHFCF 3 , CF 3 CH 2 CF 3 and CHF 2 CH 2 CF 3 and (c2) at least one saturated compound selected from halogenated hydrocarbons and ethers having the formula         C n H 2n+2-a-b Cl a F b O c wherein n is an integer from 1 to 4, a is an integer from 0 to 2n+1, b is an integer from 1 to 2n+2-a, and c is 0 or 1, provided that when c is 1 then n is an integer from 2 to 4, and provided that component (c2) does not include the selected component (c1) compound wherein the molar ratio of component (c2) to component (c1) is between about 1:99 and a molar ratio of HF to component (c1) in an azeotrope or azeotrope-like composition of component (c1) with HF, comprising: (A) combining (i) said azeotrope or azeotrope-like composition with (ii) at least one fluorination precursor compound wherein the precursor component (ii) is the fluorination precursor to component (c2);and (B) reacting a sufficient amount of the HF from the azeotrope or azeotrope-like composition (i) with precursor component (ii) to provide a composition containing components (c1) and (c2) in said ratio.
  3. 7
    An azeotropic composition comprising CF 3 CHFCF 3 and HF, wherein said HF is present in an amount of from 29.9 to 41.3 mole percent.
  4. 8
    A composition comprising:(c1) a compound selected from the group consisting of CF 3 CHFCF 3 , CF 3 CH 2 CF 3 and CHF 2 CH 2 CF 3 ;and (c2) at least two saturated compounds selected from halogenated hydrocarbons and ethers having the formula:         C n H 2n+2-a-b Cl a F b O c wherein n is an integer from 1 to 4, a is an integer from 0 to 2n+1, b is an integer from 1 to 2n+2-a, and c is 0 or 1, provided that when c is 1 then n is an integer from 2 to 4, and provided that component (c2) does not include the selected component (c1) compound and provided that c is 1 for at least one of the component (c2) compounds, wherein the molar ratio of component (c2) to component (c1) is between 1:99 and 41.3:58.7 when component (c1) is CF 3 CHFCF 3 , between 1:99 and 59:41 when component (c1) is CF 3 CH 2 CF 3 , and between 1:99 and 84:16 when component (c1) is CHF 2 CH 2 CF 3 .
  5. 9
    A process for recovering HF from a product mixture comprising HF and CF 3 CHFCF 3 , comprising:(1) distilling the product mixture to remove all products which have a lower boiling point than the lowest boiling azeotrope containing HF and CF 3 CHFCF 3 ;and (2) distilling said azeotrope to recover HF as an azeotropic composition containing HF and CF 3 CHFCF 3 .